getting the most from reactants 3.1

Question 1

raw materials

Answer 1

naturally occurring chemicals that can be used to extract starting materials for a process

Question 2

examples of raw materials

Answer 2

water, air, crude oil, salt and metal ores

Question 3

feedstock

Answer 3

a substance derived from a raw material which is used to manufacture another substance

Question 4

what should you consider during the design of an industrial process

Answer 4

• availability, sustainability and cost of feedstock
• opportunities for recycling
• energy requirements
• marketability of by products
• product yield

Question 5

availability, sustainability and cost of feedstock

Answer 5

making profit
- source the feedstock locally
loosing profit
- if feedstock had been transported from far this could effect the environment
- cost of feedstock could fluctuate
- feedstock availability could also fluctuate

Question 6

opportunities for recycling

Answer 6

making profit
- feeding unreacted materials back into reactor
loosing profit
- can be difficult to separate unreacted materials and products

Question 7

energy requirements

Answer 7

making profit
- if the reacting is exothermic it can be used to heat another reaction or the building
- catalysts are often used to speed up a reaction overheat
loosing profit
- if a reaction requires heat this is very expensive and will also have an environmental impact
- cooling a reaction can be expensive

Question 8

marketability of by products

Answer 8

making profit
- if any by products can be used else where in the process that saves money
- if by products can be sold on this generates more profit
loosing profit
- if by products are toxic or environmentally damaging it can be expensive to deal with these

Question 9

product yield

Answer 9

making profit
- a high yield increases profit
loosing profit
- if a product is low yielding this costs money as time and energy must be used to run the process multiple times

Question 10

molar volume

Answer 10

the volume of 1 mole of gas

Question 11

percentage yield

Answer 11

a measure of how much product has been produced and is a comparison of how much product was actually produced compared to how much could have theoretically been produced

Question 12

atom economy

Answer 12

measures the proportion of the total mass of all starting materials successfully converted into the desired product